A Class-G Headphone Amplifier in 65 nm CMOS Technology
A Class-G Headphone Amplifier in 65 nm CMOS Technology
复制标题
采用 65 nm CMOS 技术的 G 类耳机放大器
DOI：
10.1109/jssc.2010.2076450
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发表时间：
2010
影响因子：
5.4
通讯作者：
R. Castello
中科院分区：
文献类型：
--
作者：
Alex Lollio;G. Bollati;R. Castello
本文提出了一种基于低失真开关原理技术的G类放大器，称为开关电流注入。开关电路使得能够在电压供电轨之间非常平滑地切换，从而获得高效率和低失真。提出了一种用于评估G类放大器中的开关失真（以及环路抑制它的能力）的方法，并将所获得的结果用于优化反馈环路压缩后的总体失真。基于上述概念的集成式65 nm CMOS G类耳机驱动器采用±1.4 V和±0.35 V电源供电。在低功耗水平下，它几乎只使用低压电源，将功耗降至1.63 mW（Pout = 0.5 mW时为32 Ω）。在较高功率水平下，当使用两个电源时，供电轨之间的平滑过渡使THD + N优于-80 dB（Pout ≤ 16 mW，转换为32 Ω）。SNR为101 dB，静态功率为0.41 mW，有源芯片面积为0.14 mm 2。
This paper presents a class G amplifier based on a low distortion switching principle technique called switching currents injection. The switching circuit enables a very smooth handover between the voltage supply rails obtaining both high efficiency and low distortion. An approach for the evaluation of the switching distortion in a class G amplifier (and the ability of the loop to reject it) is proposed and the results obtained are used to optimize the overall distortion after compression by the feedback loop. The integrated 65 nm CMOS class G headphone driver based on the above concept operates from ±1.4 V and ±0.35 V supplies. At low power level it uses almost exclusively the low voltage supply reducing the dissipation to 1.63 mW @ Pout = 0.5 mW into 32 Ω. At higher power level, where both supplies are used, the smooth transition between the rails allows a THD + N better than -80 dB for Pout ≤ 16 mW into 32 Ω. The SNR is 101 dB, quiescent power is 0.41 m W and active die area is 0.14 mm2.